Thanks for the questions!
1. In computing an attacker's or defender's factors for a combat, are the triangles applied before or after you take into effect terrain and weather? I think after.
The defensive Factors (red & white triangles) are the last thing you take into account (Land Round: if defending land units can't trace a Supply Line that +2 mod occurs last, too.) So modify Factors for terrain and weather before that. Then add in the triangles.
2. In computing which side has the larger armour size (for figuring out whether an attacker can advance into an area), the size is computed by both sides before or after taking into account any step losses from combat. I think before.
Before is correct.
3.Imagine a land combat where two armour units and one infantry unit are attacking a single land unit with a one-step value. The attacker has the greater size in armour units when taking into effect terrain etc.
A. If the attacker rolls a "B" or an "L", the defender must retreat. If the attacker rolls an "S", the defender does not retreat.
Correct. (We're assuming that the defending land unit was not destroyed too.)
B. If the attacker rolls a "B" or an "L" and the defender rolls an "L" and the defender decides that the attacker's two armoured units cannot advance, the defender must still retreat and the attacker's infantry unit would occupy the area.
C. If both of the resulting dice rolls contain a "B", I understand that the attacking units must stay where they are and the defender must retreat. Even though the attacked area is now vacant the defender retains control. If the defender was not able to retreat, the defending unit would take a step loss and be eliminated, but the attacker would not be allowed to advance into the area and the defender would still keep control of the area.
Thank you very much for clearing this up for me. I am enjoying the game...which I think does a great job on so many levels.
It looks like you have a good handle on the interactions of ground combat. Thank you for the kind words. Good luck and have fun! Cheers, Dave L.